Spatial distribution and seasonality of ichthyoplankton and anthropogenic debris in a river delta in the Caribbean Sea

Abstract

Temporal changes in larval fish species composition and abundance compared with other components of the seston are described in four estuarine habitats in the Atrato Delta, Colombia. In comparison with zooplankton, fish larvae and egg density and anthropogenic debris abundance were low in the South Atrato Delta. Transparency, water temperature and chlorophyll a were the major factors influencing the spatiotemporal distribution of ichthyoplankton in the delta. The most abundant fish larvae were Astyanax sp. 1, Anchovia clupeoides, Cetengraulis edentulus, Anchoa sp., Bathygbius curacao, Dormitator maculatus, Hyporhamphus sp., Atherinella blackburni, Gobiosoma sp. 1 and Menticirrhus americanus (92·8% of total abundance). Spatial temporal analysis shows that in this delta, shrub (arracachal) and grass (eneal) habitats are important for freshwater and estuarine species, whilst mudflat and mangrove are important for estuarine species and estuarine-marine species, since most flexion and post-flexion stages of these species were found there. Anthropogenic debris density never surpassed the total ichthyoplankton density, but was ubiquitous. Shrub and mangrove habitats had higher densities of anthropogenic debris, since these are flood-stem habitats that trap solids.

Genetic Similarity of Commerson’s Anchovy across Segara Anakan Cilacap Assessed Using Randomly Amplified Polymorphic DNA (RAPD) Markers

“…Similar results were also reported by Damerau et al (2012), that low and even absence of molecular differences among populations are common in marine fish.…”

“…Anchovy will migrate from the estuarine area to the area near the beach to spawn. Planktonic larvae of anchovies will then migrate back to the estuarine site until the juvenile and adult phases (Correa-Herrera et al, 2017). Based on the nature of S. commersonnii, the difference in water salinity between East areas and Lagoon areas does not inhibit anchovy migration.…”

Dynamics of early life‐history stages of fish along an estuarine gradient

“…The larval fish assemblage found in the VB was composed of few species with high abundance and a large number of rare species, a typical characteristic of estuarine fish populations (Barletta & Barletta‐Bergan, ; Barletta‐Bergan et al., ; Correa‐Herrera, Barletta, Lima, Jiménez‐Segura, & Arango‐Sánchez, ; Ramos, Cowen, Ré, & Bordalo, ). According to Whitfield (), this relatively low species diversity is attributed to the fact that estuaries are unpredictable environments which lack any degree of permanence and are dominated by broadly adapted taxa.…”

“…I G U R E 3 Mean concentration and standard deviation (error bars) of (a) chlorophyll-a and the nutrients (b) nitrate, (c) nitrite, (d) ammonia, and (e) phosphate recorded seasonally (rainy and dry) during day-and night-time at each station (1-9) along the Vaza Barris estuarine gradientNunn, Tewson, & Cowx, 2012;Tewson, Cowx, & Nunn, 2016) and also adult spawning behavior(Reebs, 2002). On the other hand, more detailed analyses considering a species-specific circadian variation related to larval stages or lengths can clarify the role of endogenous rhythms and exogenous cues to time vertical migration(Fortier & Leggett, 1983;Boehlert & Mundy, 1988;Sclafani, Taggart, & Thompson, 1993. The larval fish assemblage found in the VB was composed of few species with high abundance and a large number of rare species, a typical characteristic of estuarine fish populations(Barletta & Barletta-Bergan, 2009;Barletta-Bergan et al, 2002;Correa-Herrera, Barletta, Lima, Jiménez-Segura, & Arango-Sánchez, 2017; …”

Stable‐isotope analysis reveals sources of organic matter and ontogenic feeding shifts of a mangrove‐dependent predator species, New Granada sea catfish, Ariopsis canteri

“…The Atrato River discharges into the western coast of the gulf and is the second‐largest freshwater input, after the Magdalena River, for the southern Caribbean (García‐Valencia, 2007). The estuary of the Atrato River Delta (ARD) is considered an essential aquatic habitat for biota and artisanal fisheries; nonetheless, information about fish is scarce (Correa‐Herrera et al ., 2016; Correa‐Herrera et al ., 2017; Sandoval et al ., 2020). There is a micro‐tidal regime with amplitude <40 cm.…”